Lubricant cooling system



Nov. 19, 1957 A. c. EISENHART 2,813,763

LUBRICANT COOLING SYSTEM Filed Aug. 9. 1954 m lllllllllll INVENTOR.

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United States Patent LUBRICANT COOLING SYSTEM Arliu C. Eisenhart, Los Angeles, Calif., assignor to U. S.

Electrical Motors, Inc., Los Angeles, Calif., a corporation of California Application August 9, 1954, Serial No. 448,638

1 Claim. (Cl. 308-77) This invention relates to a lubrication system for rotary apparatus, and especially to a system utilizing air currents for maintaining the lubricant cool.

It is an object of this invention to provide a casing structure for rotary apparatus, such as an electric motor, incorporating a lubricant well communicating with a bearing structure in which, by a simple arrangement of parts, the lubricant in the well is maintained cool.

It is another object of this invention to utilize in a simple manner a current of air created by a fan carried by the rotary structure within the casing in order to cool the lubricant. For this purpose, a series of flues or air ducts pass transversely through the lubricant well, the lubricant well being located above the fan.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of one embodiment of the invention. For this purpose, there is shown a form in the drawings accompanying and forming part of the present specification. This form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of this invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is an axial sectional view of the upper portion of a vertical electric motor incorporating the present invention;

Fig. 2 is a fragmentary sectional view, taken along the plane corresponding to line 22 of Fig. 1; and

Fig. 3 is a fragmentary sectional view, corresponding to a part of the structure shown in Fig. 1, the lubricant being omitted.

Supported within a motor casing frame are stator and rotor structures 11 and 12.

The rotor 12 has a hollow shaft 13 adapted to be coupled to a load shaft 14 located therein. For this purpose, coupling members 15 and 16 are provided at the upper ends of the shafts 13 and 14.

The shaft 13 projects axially through a bearing cup 17 that is formed integrally upon a supporting web 18. The web 18, having radially extending ribs 36 on its lower side, extends inwardly from the casing frame 10.

The cup 17 has an intermediate shoulder 19 upon which the outer race of a roller bearing structure 20 rests. The lower coupling member 16 carries the inner race of the bearing structure 20.

An annular lubricant well extends entirely about the cup 17, the lubricant well being bounded by the exterior surface of the cup 17, the interior surface of the casing frame 10, and that portion of the upper surface of the web 18 located between the cup 17 and the casing frame 10. The upper end of the casing frame 10 has a continuous flange 26 extending inwardly substantially to overlie the lubricant well.

Several angularly spaced reinforcing ribs or vanes 37 (see, particularly, Fig. 3) extend radially between the ice upper portion of the cup 17 and the casing frame 10. The lower edges of the ribs are spaced above the web 18, and joined thereat to the upper surface of a substantially annular supporting flange 27 extending outwardly from the cup 17. The flange 27 extends below the normal level of lubricant in the well, the outer edge of the flange terminating short of the casing frame 10. Openings 37a are formed in the reinforcing ribs that adjoin the flange 27 in order to ensure free circumferential movement of the lubricant at the upper levels of the well.

Lubricant may pass into the cup 17 to an annular space 21 beneath the bearing structure 20 through a plurality of radial passages 22 near the base of the cup 17. The lubricant from the annular space 21 may pass upwardly through the bearing structure and over the upper edge of the cup 17 or through a slot or port in the cup back to the lubricant well.

In order to cool the lubricant in the well, a series of ducts or flue pipes 23 are provided. These ducts 23 extend upwardly entirely through the well. Air passing through the ducts 23 conducts heat from the lubricant, the ducts 23 being made of metal material having good heat-transfer properties.

The lower ends of the ducts or flue pipes 23 sealingly fit apertures 24 provided in the web 18. The upper ends of the flue pipes 23 fit apertures 25 formed in the overlying flange 26 of the casing frame 10.

The' supporting flange 27 has apertures 28 through which the ducts 23 project with slight clearance.

In the present instance, the ducts 23 are arranged uniformly, there being one series of closely angularly spaced ducts. A different arrangement of ducts could, of course, be provided, it being essential only that the ducts permit substantial total flow of air and that the ducts have a substantial area exposed to the lubricant in the well.

The flue pipes 23 establish communication between the space beneath the web 18, in which the motor structure is accommodated, and the exterior of the casing frame 10.

Air is urged downward through the ducts or flue pipes 23 by the aid of a series of fan blades 33 fastened to the end of the rotor 12. A conical deflector 34 appropriately directs the air into the ducts.

A bell cap cover 29 has a central stepped flange 30 fitting within an annular upwardly extending terminal portion 31 of the overlying casing frame flange 26. The bell cap cover 29 has a peripheral portion or flange 32 projecting over the upper ends of the ducts 23 and downwardly along the casing frame to shield the ducts 23. This shielding flange 32 ensures against material entering into the casing frame 10 through the ducts 23, while permitting egress of air from the casing.

The inventor claims:

In a lubricant cooling system for a vertical electric motor having a fan; a casing for the motor; a partition wall extending transversely of the casing beneath the top thereof and dividing the casing into an upper space and a lower space; said wall having a centrally located apertured cup for accommodating a bearing structure and for passage of the shaft of said motor; said cup having an integrally formed outwardly extending flange provided with a series of angularly spaced openings; said upper space forming a circular lubricant reservoir into which said cup flange radially projects, said reservoir being bounded by the casing and by the cup; said casing having an inwardly extending flange overlying the marginal portion of the partition wall, and provided with a series of angularly spaced openings; said partition wall also having a series of angularly spaced openings aligned respectively with the openings of said casing flange; a series of ducts, each fitting at opposite ends an opening of the flange and the corresponding opening of the partition wall and exextending into the reservoir and having openings pertending through an opening of the cup flange; a cover mitting circular movement of lubricant in the reservoir. having a central portion fitting the terminal portion of said casing flange, exposing said ducts exteriorly of the References Clted 111 the file of thls Pawnt easing, said cover having an annular flange overlying the 5 UNITED STATES PATENTS openings of said casing flange and extending downwardly beeath the casing flange along and spaced from the ex- 1111342 Wlmams Sept 1914 1,750,898 Magnuson Mar. 18, 1930 tenor of the casing, a deflector secured to the underside 1 920 315 M as Au 1 1933 of the partition wall forming a guide for air between the openings of said partition wall and the lower spaceand 10 194S833 Swanson 1934 2,393,808 'Ponomarefi Jan. 29, 1946 a series of reinforcing vanes angularly located about the cup and joining the cup to the casing flange, said vanes 

